Improvement in wrenches



L.M"JOHNSON.

WRENCHES. No. 179,456. Patented. July 4,1876.

WITNESSES VJJJV'TOR PETERS, PHOTO-UTHDGRAPNER[WAHINGTON D G,

UNITED STATES PATENT OFFICE.

LUTHER M. JOHNSON, OF LA GRANGE, OHIO, ASSIGNOR OF ONE-HALF HIS RIGHT TOGEORGE D. JOHNSON, OF SAME PLACE.

IMPROVEMENT IN WRENCHES.

Specification forming part of Letters Patent No. 179,456, dated July 4,1876; application filed May 18, 1876.

To all whom it may concern Be it known that I, LUTHER. M. JOHNSON, of LaGrange, in the county of Lorain and State of Ohio, have invented certainnew and useful Improvements in Monkey-Wrenches; and I do hereby declarethe following to be a full, clear, and exact description of theinvention, such as will enable others skilled in the art to which itpertains to make and use it, reference being bad to the accompanyingdrawings, which form part of this specification.

My invention relates to an improvement in monkey-wrenches.

In the drawing is shown an isometric view of a wrench embodying myinvention, with parts removed, so as to show the construction andoperation of the cam serrated clamp.

My invention consists of the following parts and combinations, ashereinafter set forth and claimed, wherein A is the main arm, one end ofwhich is provided with the handle A, and to the other end of which issecurely attached the stationary jaw B. O is the movable jaw, having arear projectlon enveloping the arm A, serving the purposes of a guideand support. The

movable jaw O is provided with a ratchet arm, D, whose serrations aremade to face downward against the arm A. At any suitable position uponthe arm Ais placed a single cog or tooth, A, which engages with theratchet-bar D. E is any suitable frame or support, wherein is journaledthe cam F, operated by an arm or lever, F.. G is a latch for securingthe cam-lever Ff in its locked position.

Operation: By lifting the cam-lever F the movablejaw O is free to bemoved to any desired position, so as to accommodate nuts of differentsizes. When suitably adjusted along the arm A it is firmly secured bybringing down and latching the cam-lever F, by which operation the toothA is brought into bearing with the serrated arm of the movablejaw.

What I claim is In a monkey-wrench, the combination, with the fixed armA, of the movable jaw G, hav-' ing the rack-bar D rigidly securedthereto, and a cam-headed lever journaled in-a separate support, and acatch-bar, G, at the end of the handle nearest the jaws, as set-forth,whereby the cam, resting on the back of the rack-bar, operates to lockthe movable jaw at any desired point, without interference with thegrasping ot' the handle, substantially as and for the purpose described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

LUTHER M. JOHNSON.

Witnesses:

E. G. J OHNSON, A. J. BLANOHARD.

